It is a common practice in electric switches to utilize lamps as indicators of switch location, function or of some circuit condition of the switch contacts. A preferred method of accomplishing this is to mount the lamp in the switch operator element. Inasmuch as the operator element is normally a moving member, a problem exists in providing electrical connection to the lamp. In designs where lamps having metallic bases are used, formed terminal members are provided which have a hinge or brush electrical connection with the moving lamp. A trend towards miniaturization of switches and lamps alike has produced incandescent lamp bulbs having no metallic base, but thin wire leads extending therefrom. The size of such lamps facilitates their use in switch operators, but the fragility of the lamp leads requires particular design attention to the commutation means for conducting electrical current to these leads. One method has been to provide conducting sleeves over the leads to increase their rigidity while other methods provide helical springs to bear against the leads and make electrical contact therewith. The latter approach provides "dry circuit" conditions which are susceptible to contamination and circuit failure, while the added sleeve approach requires the production and assembly of additional separate parts to the switch, thereby increasing the manufacturing cost thereof.
The introduction of solid state lamp devices such as light emitting diodes has generated new approaches to the methods of providing electrical connections thereto in view of the more substantial and more rigid electrical leads of such diodes. U.S. Pat. No. 4,115,673 uses a light emitting diode in a rocker button and causes the relatively short but unsupported leads of the diode to move into or out of engagement with upstanding contact members on the switch itself to make electrical connection to the lead when the switch is moved to one position and to break that electrical connection when the switch rocker is moved to its opposite position.
Push-button switches have particular problems and concerns when providing commutation to button-mounted lamp devices and the leads therefore. One particular consideration is that the distance between lamp contacts and the lamp is significantly increased because of the need for additional switch mechanism between the contact actuator and the operator. Another concern is the location of the lamp element on the face of the button and the ability to route the lamp leads through the switch body without adversely effecting the switch mechanism.